Jessica Hume, National Bureau

OTTAWA — The NDP used its last opposition day this session to rail against the government's proposal to allow income splitting, saying it would help too few Canadians and not those most in need.

Income splitting allows couples to redistribute their wealth in order to pay less tax. During the last election, the Conservatives promised that once the budget is balanced they would allow spouses with children under age 18 to share up to $50,000 of their income, which means the higher earner could shift income to their spouse in a lower tax bracket.

A new study from the left-leaning Broadbent Institute found nine out of 10 households would receive no benefit from the policy. "It would increase inequality and is skewed heavily toward a Mad Men-style family with a high-income earner and a stay-at-home spouse," Broadbent director Rick Smith said.